As America's population ages, the incidence of age-related dementia is rising. According to a 2010 study in “Alzheimer’s Research and Therapy,” your chance of developing Alzheimer’s dementia doubles every five years after the age of 60 and continues to rise into extreme old age. But Alzheimer’s disease is only one example of how the human mind can falter. Even if you are young and vital, your brain is a fragile and metabolically demanding organ. Supplying it with good nutrition throughout your lifetime is one way to ensure its optimal function.
Healthy Body, Healthy Brain
Your brain is subjected to the same physiologic environment that surrounds the rest of your organs. Cerebrovascular disease, which is the brain’s equivalent of coronary heart disease, is a common cause of cognitive decline. Like coronary heart disease, cerebrovascular disease results largely from lifestyle choices and it can impair your mental function long before you completely lose your memory. The American Heart Association urges you to lower your fat consumption to less than 30 percent of your total daily caloric intake. Saturated fats and trans fats should account for less than 7 percent and 1 percent, respectively, of your total daily caloric consumption. The AHA diet is rich in complex carbohydrates, whole grains, fruits and vegetables, and it supplies two weekly meals of cold-water fish. Although these guidelines were designed to keep your heart healthy, a 2007 study published in “Neurology” demonstrated that your brain can benefit from a healthy diet, too.
Neurotransmitters from Brain Foods
Your brain functions by relaying impulses from one nerve cell, or neuron, to another. This process is dependent on an adequate supply of neurotransmitters, which are chemical messengers that serve to carry impulses across tiny gaps, called synapses, which separate the neurons. Neurotransmitters are synthesized within the neurons from precursor molecules that are obtained from your diet. A well-balanced diet usually is sufficient to ensure good brain function, but some foods are better sources of essential precursors than others.
Serotonin
Serotonin is a neurotransmitter that serves myriad roles in the brain. Its influences on mood, sleep, appetite, pain perception and socialization have made it the subject of extensive research. Serotonin is synthesized in the brain from L-tryptophan, an amino acid found in meats, milk, eggs, legumes, flaxseed, nuts, lentils and soy. L-tryptophan is not found in large amounts in any food, however, so some people choose to take a supplement.
Catecholamines
Norepinephrine, epinephrine and dopamine are catecholamine neurotransmitters and neurohormones that serve a variety of functions both inside and outside of the brain. They participate in the autonomic nervous system’s “fight-or-flight” response, and they help to regulate movement, motivation, learning, memory, sleep, blood pressure, heart rate and other physiologic and behavioral activities. The catecholamines are synthesized from the non-essential amino acid tyrosine, which in turn is manufactured in your body from the essential amino acid phenylalanine. Eggs, fish, dairy products, sesame seeds and spirulina, a form of seaweed, are good food sources of tyrosine. Tyrosine supplements also are commercially available.
Supporting Cells
The cells that surround and support the neurons have their own needs. According to Dr. Fernando Gomez-Pinilla, a professor of neurosurgery at UCLA, your brain is more metabolically active than any other organ in your body. This high rate of energy consumption makes the brain highly susceptible to damage caused by oxidation. A diet that is rich in fruits, vegetables and other sources of antioxidants, vitamins and minerals can help to prevent much of this damage. Omega-3 fatty acids, specifically docosahexaenoic acid, or DHA, are crucial for maintaining synaptic “plasticity,” a property that improves learning and memory. Algae and oily fish, such as salmon, mackerel or herring, are good sources of DHA.
Recommendations
Although you might be tempted to tailor your diet around specific foods and supplements to improve your brain’s function, the most important behaviors you can adopt for brain health are those that keep your heart and other organs healthy. An AHA diet is a good start, but you might prefer a Mediterranean diet, which includes larger amounts of monounsaturated fats. If you smoke, quit. Exercise daily. If you want to add brain-building supplements to your regimen, consider L-tryptophan or 5-HTP, which are used to synthesize serotonin, or L-tyrosine, which is the precursor for the catecholamines. Take a daily omega-3 supplement or eat two oily fish meals per week. Finally, take your brain out for a spin from time to time, for it, too, needs some exercise.
References
- “Alzheimer’s Research and Therapy”; Increasing incidence of dementia in the oldest old: evidence and implications; James B, Schneider J; 2010
- HealthCastle.com: Heart Association revises diet recommendations
- “Neurology”; Mediterranean diet and Alzheimer disease mortality; Scarmeas N, et al.; 2007
- “Nature Reviews: Neuroscience”; Brain foods: the effects of nutrients on brain function; Gomez-Pinilla F; 2008
